This invention relates to a bubble-forming apparatus, more particularly to a venturi-tube type bubble-forming container.
The high-pressure vapor produced by espresso coffee makers has been used for drawing a beverage, such as milk and juice, into a container so as to bubble the same according to the principle of venturi tube. The improvement of this invention is directed to a conventional venturi-tube type bubble-forming container such as that shown in FIGS. 1 and 2. As illustrated, the container C includes a vertical connecting pipe Cl secured to the upper end thereof which engages with the vapor or main pipe B of an espresso coffee maker A. The container C has a funnel-like inlet C2 which forms the throat of the vapor passage. A branch pipe C3 is provided in communication with the inlet C2 and a beverage container so that, when high-pressure vapor flows from the coffee maker A into the interior chamber C5 of the container C, the beverage is drawn into the chamber C5. When the steam of the beverage pounds on the inner wall of the container C, a turbulence is created in the liquid forming the beverage so as to form bubbles in the beverage. A vent hole C4 is also communicated with the inlet C2 of the container C. A discharge pipe C6 is provided at the lower end of the container C and is used for entry of the bubbled liquid into a collecting glass which is disposed immediately below the discharge pipe C6. A portion of the liquid from the inlet C2 directly flows into the discharge C6 and thus hardly forms bubbles. Although the remaining portion of the liquid flows along the inner wall of the container C, the period of moving the liquid in the container C is too short to efficiently form bubbles.